Aggression Flashcards
1
Q
Which areas of the brain have been linked to aggression
A
- limbic system
- temporal lobe
2
Q
Limbic system- what it is
A
- helps co-ordinate behaviour especially emotion and motivation
- key emotions are aggression and fear
3
Q
What are the two parts of the brain made up of for the limbic system
A
Amygdala
Hippocampus
4
Q
Amygdala- what it is
A
- gives us anger
- fast immediate response when in a situation
- very primitive part of the brain
- artificially stimulate and animals amygdala they will no longer experience rage
5
Q
Hippocampus- what is it
A
- memory- learn suitable responses based on past experiences
- responsible for memory
- damage to the hippocami can affect our normal response to aggression stimuli
6
Q
Serotonin- what is it
A
A neurotransmitter which is linked to the inhibition of emotional reactions to stimuli by inhibiting the amygdala.
7
Q
Serotonin- explanation
A
- higher serotonin means you are more able to resist and emotional response
- lower levels means more likely to react in an emotional way
- level of serotonin activity in the brain is measured by turnover- how much is produced and then broken down
8
Q
Evaluating neural influences on aggression
Positives
A
- there is a lot of evidence from animal studies that low serotonin turnover is linked to an increase in aggression
- Higley et al studied a group of 49 rhesus monkeys over 4 years. They determined each individual’s serotonin turnover. Monkeys with lower serotonin were observed to be more aggressive. After 4 years 11 monkeys had died or were missing. All of the monkeys in the highest serotonin turnover survived and the 4 who had died because of aggressive encounters were all in the lowest group
9
Q
Evaluating neural influences
Negatives
A
- lots of evidence saying serotonin is linked to aggression, lacking when it comes to them saying it causes aggression
- animal studies show a strong link between low serotonin and aggression, doesn’t mean the link is the cause
- also can’t generalise animals to humans
- lab studies have low ecological validity
10
Q
Testosterone- what is it
A
- a hormone which is significantly more plentiful in men then women.
- levels peak in young men from adolescence onwards, before declining through adulthood
- Responsible for the development of make characteristics
11
Q
Why is testosterone linked to aggression
A
- men are statistically more likely to engage in violence
- they become more aggressive when they hit puberty
- it has been argued that this indicates testosterone is related to aggression
12
Q
Evaluation of testosterone
Positives
A
- prison inmates who were convicted of violent crimes had significantly higher testosterone levels than those with non-violent convictions (Dabbs et al).
- testosterone levels fluctuate due to events and social changes in aggression through the activation of the amygdala (carre and Olmstead)
13
Q
Evaluating testosterone
Negatives
A
- evidence doesn’t always suggest that testosterone has a direct link to aggressive behaviour
- prob.em with establishing cause and effect- this data (Dabbs) is only correlational
- another factor could be causing aggression
- Van Goozen et al, studied the effects of testosterone directly, this avoided having to depend on correlational data, which makes it easier to establish cause and effect
14
Q
Genetic factors
What are concordance rates
A
- this is the percentage given to a persons likelihood of developing a characteristic based on the prevalence of it in their family
15
Q
Genetic factors
Main points
A
- family studies in aggression into concordance rates of aggressive tendencies.
- cannot know how much is inherited or how much is due to the environmental factors
- conducted twin and adoption studies
16
Q
Genetic factors
Why do we use twin and adoption studies
A
To separate nature and nurture
Genes and environment
17
Q
Genetic factors
Why are twin studies useful
A
- can compare concordance rate of MZ and dz twins
- if both MZ twins inherite aggression and show aggressive behaviour more likely to be nature because both of them have it which shows it more to do with genes then environment
- this can be applied the other way round as well
18
Q
Genetic factors
Describe the study and findings for Christiansen et al
A
- analysis of criminality in 3586 pairs of twins- 1881-1910 in Denmark
- 926 individuals were registered by the police for criminal activity
- MZ and dz twins were compared for the rate of which both twins were registered
- male MZ twins- 35% compared to 12% DZ
- female MZ twins- 21% compared to 8% dz
- twins of criminality are more likely to also be criminals if they share all of their twins DNA
- genetic component to aggressive behaviour
19
Q
Genetics
Evaluation of Christiansen study
A
:( genetics can’t be the only factor- wants 100% concordance rate
20
Q
Genetics
Why do we use adoption studies
A
- to solve the issues of twin studies by comparing the aggression rates of children who have been reared apart from their parents
- involves comparing the rates of aggression of adoptees with their biological parents
- if we find a strong concordance rate suggests they did not learn their aggression through the environment
21
Q
Genetics
Describe the study of Hutchings and Mednick
A
- large scale adoption study in Denmark- 14,000 participants
- significant proportion of male adoptees who went on to have criminal convictions for violent behaviour had biological parents who had criminal convictions for violent behaviour
22
Q
What is MAOA
A
- an enzyme involved in processing neurotransmitters, including serotonin in the brain
- the MAOA gene controls production of MAOA
- some versions of the gene which results in lower levels of MAOA have been linked to aggressive activity
23
Q
Briefly explain the role of MAOA and its link to aggressive behaviour
A
- regulates metabolism of serotonin in the brain
- low levels of serotonin are associated with impulsive and aggressive behaviour
24
Q
Outline the Brunner Dutch family
MAOA
A
- extended family in the Netherlands
- several male family members showed patterns of behaviour involving impulsive aggression including violent crime
- identified a fault in the MAOA gene of the individuals showing impulsive aggression- wasn’t present in other male family members
- low levels of MAOA
25
Limitation with the Brunner et al study
- small sample size - low population validity also because only done in Netherlands
- same family- same upbringing
26
Explain the difference between MAOA-H and MAOA-L
H- high levels of MAOA
| L- low levels of MAOA
27
Strengths of genetic factors in aggression
:) can explain gender differences
- MAOA gene can explain uneven rates of violence for males/females
- may be a consequence of the differential genetic vulnerability that makes and females have to the genes
- linked to X chromosomes
:) research support
- recent study in Finland
- prisoners
- MAOA low activity - extrem,y violent behaviour
- no evidence of either of these genes among non- violent offenders
28
Weaknesses for genetic explanation for aggression
:( difficult to measure aggression
- many of the studies have relied on self report which is t very reliable as people lie
:( ignores social and environmental factors which may play a part too
29
What is ethology
The study of animal behaviour
- often studied in order to have a better understanding of human behaviour
- it can remove many complicating factors such as speech, consciousness and societal factors
30
What did Tinbergen theorise
- all members of an animal species have in built behaviours which do not require learning
- these behaviours will occur under specific circumstances
31
What are fixed action patterns
An instinctive behaviour which is identical across a species
32
What are innate releasing mechanisms
A proposed innate pathway in the brain which sets off a fixed action pattern
33
Give some examples of innate animal behaviour
Walking
Breathing
Drinking
